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<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Zmanim Java API<a name="line.2"></a>
<FONT color="green">003</FONT>     * Copyright (C) 2004-2008 Eliyahu Hershfeld<a name="line.3"></a>
<FONT color="green">004</FONT>     *<a name="line.4"></a>
<FONT color="green">005</FONT>     * This program is free software; you can redistribute it and/or modify it under the terms of the<a
        name="line.5"></a>
<FONT color="green">006</FONT>     * GNU General Public License as published by the Free Software Foundation; either version 2 of the<a
        name="line.6"></a>
<FONT color="green">007</FONT>     * License, or (at your option) any later version.<a name="line.7"></a>
<FONT color="green">008</FONT>     *<a name="line.8"></a>
<FONT color="green">009</FONT>     * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without<a
        name="line.9"></a>
<FONT color="green">010</FONT>     * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU<a
        name="line.10"></a>
<FONT color="green">011</FONT>     * General Public License for more details.<a name="line.11"></a>
<FONT color="green">012</FONT>     *<a name="line.12"></a>
<FONT color="green">013</FONT>     * You should have received a copy of the GNU General Public License along with this program; if<a
        name="line.13"></a>
<FONT color="green">014</FONT>     * not, write to the Free Software Foundation, Inc. 59 Temple Place - Suite 330, Boston, MA<a
        name="line.14"></a>
<FONT color="green">015</FONT>     * 02111-1307, USA or connect to: http://www.fsf.org/copyleft/gpl.html<a
        name="line.15"></a>
<FONT color="green">016</FONT>     */<a name="line.16"></a>
<FONT color="green">017</FONT>    package net.sourceforge.zmanim.util;<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>    import net.sourceforge.zmanim.AstronomicalCalendar;<a name="line.19"></a>
<FONT color="green">020</FONT>    import java.util.Calendar;<a name="line.20"></a>
<FONT color="green">021</FONT>    <a name="line.21"></a>
<FONT color="green">022</FONT>    /**<a name="line.22"></a>
<FONT color="green">023</FONT>     * Implementation of sunrise and sunset methods to calculate astronomical times.<a
        name="line.23"></a>
<FONT color="green">024</FONT>     * This calculator uses the Java algorithm written by &lt;a<a name="line.24"></a>
<FONT color="green">025</FONT>     * href="http://www.jstot.me.uk/jsuntimes/"&gt;Jonathan Stott&lt;/a&gt; that is based on<a
        name="line.25"></a>
<FONT color="green">026</FONT>     * the implementation by &lt;a href=""http://noaa.gov"&gt;NOAA - National Oceanic and<a
        name="line.26"></a>
<FONT color="green">027</FONT>     * Atmospheric Administration&lt;/a&gt;'s &lt;a href =<a name="line.27"></a>
<FONT color="green">028</FONT>     * "http://www.srrb.noaa.gov/highlights/sunrise/sunrisehtml"&gt;Surface Radiation<a
        name="line.28"></a>
<FONT color="green">029</FONT>     * Research Branch&lt;/a&gt;. NOAA's &lt;a<a name="line.29"></a>
<FONT color="green">030</FONT>     * href="http://www.srrb.noaa.gov/highlights/sunrise/solareqns.PDF"&gt;implementation&lt;/a&gt;<a
        name="line.30"></a>
<FONT color="green">031</FONT>     * is based on equations from &lt;a<a name="line.31"></a>
<FONT color="green">032</FONT>     * href="http://www.willbell.com/math/mc1.htm"&gt;Astronomical Algorithms&lt;/a&gt; by<a
        name="line.32"></a>
<FONT color="green">033</FONT>     * &lt;a href="http://en.wikipedia.org/wiki/Jean_Meeus"&gt;Jean Meeus&lt;/a&gt;. Jonathan's<a
        name="line.33"></a>
<FONT color="green">034</FONT>     * implementation was released under the GPL. Added to the algorithm is an<a
        name="line.34"></a>
<FONT color="green">035</FONT>     * adjustment of the zenith to account for elevation.<a name="line.35"></a>
<FONT color="green">036</FONT>     *<a name="line.36"></a>
<FONT color="green">037</FONT>     * @author Jonathan Stott 2000 - 2004<a name="line.37"></a>
<FONT color="green">038</FONT>     * @author &amp;copy; Eliyahu Hershfeld 2004 - 2008<a name="line.38"></a>
<FONT color="green">039</FONT>     * @version 1.1<a name="line.39"></a>
<FONT color="green">040</FONT>     * @deprecated This class is based on the NOAA algorithm but does not return calculations that match the NOAA algorithm JavaScript implementation. The calculations are about 2 minutes off. This call has been replaced by the NOAACalculator class.<a
        name="line.40"></a>
<FONT color="green">041</FONT>     * @see net.sourceforge.zmanim.util.NOAACalculator<a name="line.41"></a>
<FONT color="green">042</FONT>     */<a name="line.42"></a>
<FONT color="green">043</FONT>    public class JSuntimeCalculator extends AstronomicalCalculator {<a name="line.43"></a>
<FONT color="green">044</FONT>            private String calculatorName =  "US National Oceanic and Atmospheric Administration Algorithm";<a
        name="line.44"></a>
<FONT color="green">045</FONT>            /**<a name="line.45"></a>
<FONT color="green">046</FONT>             * @deprecated This class is based on the NOAA algorithm but does not return calculations that match the NOAA algorithm JavaScript implementation. The calculations are about 2 minutes off. This call has been replaced by the NOAACalculator class.<a
        name="line.46"></a>
<FONT color="green">047</FONT>             * @see net.sourceforge.zmanim.util.NOAACalculator#getCalculatorName()<a
        name="line.47"></a>
<FONT color="green">048</FONT>             */<a name="line.48"></a>
<FONT color="green">049</FONT>            public String getCalculatorName() {<a name="line.49"></a>
<FONT color="green">050</FONT>                    return calculatorName;<a name="line.50"></a>
<FONT color="green">051</FONT>            }<a name="line.51"></a>
<FONT color="green">052</FONT>    <a name="line.52"></a>
<FONT color="green">053</FONT>            /**<a name="line.53"></a>
<FONT color="green">054</FONT>             * @deprecated This class is based on the NOAA algorithm but does not return calculations that match the NOAA algorithm JavaScript implementation. The calculations are about 2 minutes off. This call has been replaced by the NOAACalculator class.<a
        name="line.54"></a>
<FONT color="green">055</FONT>             * @see net.sourceforge.zmanim.util.NOAACalculator#getUTCSunrise(AstronomicalCalendar, double, boolean)<a
        name="line.55"></a>
<FONT color="green">056</FONT>             * @see net.sourceforge.zmanim.util.AstronomicalCalculator#getUTCSunrise(AstronomicalCalendar,<a
        name="line.56"></a>
<FONT color="green">057</FONT>             *      double, boolean)<a name="line.57"></a>
<FONT color="green">058</FONT>             * @throws ZmanimException<a name="line.58"></a>
<FONT color="green">059</FONT>             *             if the year entered == 2000. This calculator can't properly<a
        name="line.59"></a>
<FONT color="green">060</FONT>             *             deal with the year 2000. It can properly calculate times for<a
        name="line.60"></a>
<FONT color="green">061</FONT>             *             years &lt;&gt; 2000.<a name="line.61"></a>
<FONT color="green">062</FONT>             */<a name="line.62"></a>
<FONT color="green">063</FONT>            public double getUTCSunrise(AstronomicalCalendar astronomicalCalendar, double zenith, boolean adjustForElevation) {<a
        name="line.63"></a>
<FONT color="green">064</FONT>    //              if (astronomicalCalendar.getCalendar().get(Calendar.YEAR) == 2000) {<a
        name="line.64"></a>
<FONT color="green">065</FONT>    //                      throw new ZmanimException(<a name="line.65"></a>
<FONT color="green">066</FONT>    //                                      "JSuntimeCalculator can not calculate times for the year 2000. Please try a date with a different year.");<a
        name="line.66"></a>
<FONT color="green">067</FONT>    //              }<a name="line.67"></a>
<FONT color="green">068</FONT>    <a name="line.68"></a>
<FONT color="green">069</FONT>                    if (adjustForElevation) {<a name="line.69"></a>
<FONT color="green">070</FONT>                            zenith = adjustZenith(zenith, astronomicalCalendar.getGeoLocation()<a
        name="line.70"></a>
<FONT color="green">071</FONT>                                            .getElevation());<a name="line.71"></a>
<FONT color="green">072</FONT>                    } else {<a name="line.72"></a>
<FONT color="green">073</FONT>                            zenith = adjustZenith(zenith, 0);<a name="line.73"></a>
<FONT color="green">074</FONT>                    }<a name="line.74"></a>
<FONT color="green">075</FONT>                    double timeMins = morningPhenomenon(dateToJulian(astronomicalCalendar<a
        name="line.75"></a>
<FONT color="green">076</FONT>                                    .getCalendar()), astronomicalCalendar.getGeoLocation()<a
        name="line.76"></a>
<FONT color="green">077</FONT>                                    .getLatitude(), -astronomicalCalendar.getGeoLocation()<a
        name="line.77"></a>
<FONT color="green">078</FONT>                                    .getLongitude(), zenith);<a name="line.78"></a>
<FONT color="green">079</FONT>                    return timeMins / 60;<a name="line.79"></a>
<FONT color="green">080</FONT>            }<a name="line.80"></a>
<FONT color="green">081</FONT>    <a name="line.81"></a>
<FONT color="green">082</FONT>            /**<a name="line.82"></a>
<FONT color="green">083</FONT>             * @deprecated  This class is based on the NOAA algorithm but does not return calculations that match the NOAAA algorithm JavaScript implementation. The calculations are about 2 minutes off. This call has been replaced by the NOAACalculator class.<a
        name="line.83"></a>
<FONT color="green">084</FONT>             * @see net.sourceforge.zmanim.util.NOAACalculator#getUTCSunset(AstronomicalCalendar, double, boolean)<a
        name="line.84"></a>
<FONT color="green">085</FONT>             * @see net.sourceforge.zmanim.util.AstronomicalCalculator#getUTCSunset(AstronomicalCalendar,<a
        name="line.85"></a>
<FONT color="green">086</FONT>             *      double, boolean)<a name="line.86"></a>
<FONT color="green">087</FONT>             * @throws ZmanimException<a name="line.87"></a>
<FONT color="green">088</FONT>             *             if the year entered == 2000. This calculator can't properly<a
        name="line.88"></a>
<FONT color="green">089</FONT>             *             deal with the year 2000. It can properly calculate times for<a
        name="line.89"></a>
<FONT color="green">090</FONT>             *             years &lt;&gt; 2000.<a name="line.90"></a>
<FONT color="green">091</FONT>             */<a name="line.91"></a>
<FONT color="green">092</FONT>            public double getUTCSunset(AstronomicalCalendar astronomicalCalendar, double zenith, boolean adjustForElevation) {<a
        name="line.92"></a>
<FONT color="green">093</FONT>    //              if (astronomicalCalendar.getCalendar().get(Calendar.YEAR) == 2000) {<a
        name="line.93"></a>
<FONT color="green">094</FONT>    //                      throw new ZmanimException(<a name="line.94"></a>
<FONT color="green">095</FONT>    //                                      "JSuntimeCalculator can not calculate times for the year 2000. Please try a date with a different year.");<a
        name="line.95"></a>
<FONT color="green">096</FONT>    //              }<a name="line.96"></a>
<FONT color="green">097</FONT>    <a name="line.97"></a>
<FONT color="green">098</FONT>                    if (adjustForElevation) {<a name="line.98"></a>
<FONT color="green">099</FONT>                            zenith = adjustZenith(zenith, astronomicalCalendar.getGeoLocation()<a
        name="line.99"></a>
<FONT color="green">100</FONT>                                            .getElevation());<a name="line.100"></a>
<FONT color="green">101</FONT>                    } else {<a name="line.101"></a>
<FONT color="green">102</FONT>                            zenith = adjustZenith(zenith, 0);<a name="line.102"></a>
<FONT color="green">103</FONT>                    }<a name="line.103"></a>
<FONT color="green">104</FONT>                    double timeMins = eveningPhenomenon(dateToJulian(astronomicalCalendar<a
        name="line.104"></a>
<FONT color="green">105</FONT>                                    .getCalendar()), astronomicalCalendar.getGeoLocation()<a
        name="line.105"></a>
<FONT color="green">106</FONT>                                    .getLatitude(), -astronomicalCalendar.getGeoLocation()<a
        name="line.106"></a>
<FONT color="green">107</FONT>                                    .getLongitude(), zenith);<a name="line.107"></a>
<FONT color="green">108</FONT>                    return timeMins / 60;<a name="line.108"></a>
<FONT color="green">109</FONT>            }<a name="line.109"></a>
<FONT color="green">110</FONT>    <a name="line.110"></a>
<FONT color="green">111</FONT>            /**<a name="line.111"></a>
<FONT color="green">112</FONT>             * Calculate the UTC of a morning phenomenon for the given day at the given<a
        name="line.112"></a>
<FONT color="green">113</FONT>             * latitude and longitude on Earth<a name="line.113"></a>
<FONT color="green">114</FONT>             *<a name="line.114"></a>
<FONT color="green">115</FONT>             * @param julian<a name="line.115"></a>
<FONT color="green">116</FONT>             *            Julian day<a name="line.116"></a>
<FONT color="green">117</FONT>             * @param latitude<a name="line.117"></a>
<FONT color="green">118</FONT>             *            latitude of observer in degrees<a name="line.118"></a>
<FONT color="green">119</FONT>             * @param longitude<a name="line.119"></a>
<FONT color="green">120</FONT>             *            longitude of observer in degrees<a name="line.120"></a>
<FONT color="green">121</FONT>             * @param zenithDistance<a name="line.121"></a>
<FONT color="green">122</FONT>             *            one of Sun.SUNRISE_SUNSET_ZENITH_DISTANCE,<a
        name="line.122"></a>
<FONT color="green">123</FONT>             *            Sun.CIVIL_TWILIGHT_ZENITH_DISTANCE,<a name="line.123"></a>
<FONT color="green">124</FONT>             *            Sun.NAUTICAL_TWILIGHT_ZENITH_DISTANCE,<a name="line.124"></a>
<FONT color="green">125</FONT>             *            Sun.ASTRONOMICAL_TWILIGHT_ZENITH_DISTANCE.<a
        name="line.125"></a>
<FONT color="green">126</FONT>             * @return time in minutes from zero Z<a name="line.126"></a>
<FONT color="green">127</FONT>             */<a name="line.127"></a>
<FONT color="green">128</FONT>            private static double morningPhenomenon(double julian, double latitude,<a
        name="line.128"></a>
<FONT color="green">129</FONT>                            double longitude, double zenithDistance) {<a
        name="line.129"></a>
<FONT color="green">130</FONT>                    double t = julianDayToJulianCenturies(julian);<a name="line.130"></a>
<FONT color="green">131</FONT>                    double eqtime = equationOfTime(t);<a name="line.131"></a>
<FONT color="green">132</FONT>                    double solarDec = sunDeclination(t);<a name="line.132"></a>
<FONT color="green">133</FONT>                    double hourangle = hourAngleMorning(latitude, solarDec, zenithDistance);<a
        name="line.133"></a>
<FONT color="green">134</FONT>                    double delta = longitude - Math.toDegrees(hourangle);<a
        name="line.134"></a>
<FONT color="green">135</FONT>                    double timeDiff = 4 * delta;<a name="line.135"></a>
<FONT color="green">136</FONT>                    double timeUTC = 720 + timeDiff - eqtime;<a name="line.136"></a>
<FONT color="green">137</FONT>    <a name="line.137"></a>
<FONT color="green">138</FONT>                    // Second pass includes fractional julian day in gamma calc<a
        name="line.138"></a>
<FONT color="green">139</FONT>                    double newt = julianDayToJulianCenturies(julianCenturiesToJulianDay(t)<a
        name="line.139"></a>
<FONT color="green">140</FONT>                                    + timeUTC / 1440);<a name="line.140"></a>
<FONT color="green">141</FONT>                    eqtime = equationOfTime(newt);<a name="line.141"></a>
<FONT color="green">142</FONT>                    solarDec = sunDeclination(newt);<a name="line.142"></a>
<FONT color="green">143</FONT>                    hourangle = hourAngleMorning(latitude, solarDec, zenithDistance);<a
        name="line.143"></a>
<FONT color="green">144</FONT>                    delta = longitude - Math.toDegrees(hourangle);<a name="line.144"></a>
<FONT color="green">145</FONT>                    timeDiff = 4 * delta;<a name="line.145"></a>
<FONT color="green">146</FONT>    <a name="line.146"></a>
<FONT color="green">147</FONT>                    double morning = 720 + timeDiff - eqtime;<a name="line.147"></a>
<FONT color="green">148</FONT>                    return morning;<a name="line.148"></a>
<FONT color="green">149</FONT>            }<a name="line.149"></a>
<FONT color="green">150</FONT>    <a name="line.150"></a>
<FONT color="green">151</FONT>            /**<a name="line.151"></a>
<FONT color="green">152</FONT>             * Calculate the UTC of an evening phenomenon for the given day at the given<a
        name="line.152"></a>
<FONT color="green">153</FONT>             * latitude and longitude on Earth<a name="line.153"></a>
<FONT color="green">154</FONT>             *<a name="line.154"></a>
<FONT color="green">155</FONT>             * @param julian<a name="line.155"></a>
<FONT color="green">156</FONT>             *            Julian day<a name="line.156"></a>
<FONT color="green">157</FONT>             * @param latitude<a name="line.157"></a>
<FONT color="green">158</FONT>             *            latitude of observer in degrees<a name="line.158"></a>
<FONT color="green">159</FONT>             * @param longitude<a name="line.159"></a>
<FONT color="green">160</FONT>             *            longitude of observer in degrees<a name="line.160"></a>
<FONT color="green">161</FONT>             * @param zenithDistance<a name="line.161"></a>
<FONT color="green">162</FONT>             *            one of Sun.SUNRISE_SUNSET_ZENITH_DISTANCE,<a
        name="line.162"></a>
<FONT color="green">163</FONT>             *            Sun.CIVIL_TWILIGHT_ZENITH_DISTANCE,<a name="line.163"></a>
<FONT color="green">164</FONT>             *            Sun.NAUTICAL_TWILIGHT_ZENITH_DISTANCE,<a name="line.164"></a>
<FONT color="green">165</FONT>             *            Sun.ASTRONOMICAL_TWILIGHT_ZENITH_DISTANCE.<a
        name="line.165"></a>
<FONT color="green">166</FONT>             * @return time in minutes from zero Z<a name="line.166"></a>
<FONT color="green">167</FONT>             */<a name="line.167"></a>
<FONT color="green">168</FONT>            private static double eveningPhenomenon(double julian, double latitude,<a
        name="line.168"></a>
<FONT color="green">169</FONT>                            double longitude, double zenithDistance) {<a
        name="line.169"></a>
<FONT color="green">170</FONT>                    double t = julianDayToJulianCenturies(julian);<a name="line.170"></a>
<FONT color="green">171</FONT>    <a name="line.171"></a>
<FONT color="green">172</FONT>                    // First calculates sunrise and approx length of day<a
        name="line.172"></a>
<FONT color="green">173</FONT>                    double eqtime = equationOfTime(t);<a name="line.173"></a>
<FONT color="green">174</FONT>                    double solarDec = sunDeclination(t);<a name="line.174"></a>
<FONT color="green">175</FONT>                    double hourangle = hourAngleEvening(latitude, solarDec, zenithDistance);<a
        name="line.175"></a>
<FONT color="green">176</FONT>    <a name="line.176"></a>
<FONT color="green">177</FONT>                    double delta = longitude - Math.toDegrees(hourangle);<a
        name="line.177"></a>
<FONT color="green">178</FONT>                    double timeDiff = 4 * delta;<a name="line.178"></a>
<FONT color="green">179</FONT>                    double timeUTC = 720 + timeDiff - eqtime;<a name="line.179"></a>
<FONT color="green">180</FONT>    <a name="line.180"></a>
<FONT color="green">181</FONT>                    // first pass used to include fractional day in gamma calc<a
        name="line.181"></a>
<FONT color="green">182</FONT>                    double newt = julianDayToJulianCenturies(julianCenturiesToJulianDay(t)<a
        name="line.182"></a>
<FONT color="green">183</FONT>                                    + timeUTC / 1440);<a name="line.183"></a>
<FONT color="green">184</FONT>                    eqtime = equationOfTime(newt);<a name="line.184"></a>
<FONT color="green">185</FONT>                    solarDec = sunDeclination(newt);<a name="line.185"></a>
<FONT color="green">186</FONT>                    hourangle = hourAngleEvening(latitude, solarDec, zenithDistance);<a
        name="line.186"></a>
<FONT color="green">187</FONT>    <a name="line.187"></a>
<FONT color="green">188</FONT>                    delta = longitude - Math.toDegrees(hourangle);<a name="line.188"></a>
<FONT color="green">189</FONT>                    timeDiff = 4 * delta;<a name="line.189"></a>
<FONT color="green">190</FONT>    <a name="line.190"></a>
<FONT color="green">191</FONT>                    double evening = 720 + timeDiff - eqtime;<a name="line.191"></a>
<FONT color="green">192</FONT>                    return evening;<a name="line.192"></a>
<FONT color="green">193</FONT>            }<a name="line.193"></a>
<FONT color="green">194</FONT>    <a name="line.194"></a>
<FONT color="green">195</FONT>            private static double dateToJulian(Calendar date) {<a name="line.195"></a>
<FONT color="green">196</FONT>                    int year = date.get(Calendar.YEAR);<a name="line.196"></a>
<FONT color="green">197</FONT>                    int month = date.get(Calendar.MONTH) + 1;<a name="line.197"></a>
<FONT color="green">198</FONT>                    int day = date.get(Calendar.DAY_OF_MONTH);<a name="line.198"></a>
<FONT color="green">199</FONT>                    int hour = date.get(Calendar.HOUR_OF_DAY);<a name="line.199"></a>
<FONT color="green">200</FONT>                    int minute = date.get(Calendar.MINUTE);<a name="line.200"></a>
<FONT color="green">201</FONT>                    int second = date.get(Calendar.SECOND);<a name="line.201"></a>
<FONT color="green">202</FONT>    <a name="line.202"></a>
<FONT color="green">203</FONT>                    double extra = (100.0 * year) + month - 190002.5;<a
        name="line.203"></a>
<FONT color="green">204</FONT>                    double JD = (367.0 * year)<a name="line.204"></a>
<FONT color="green">205</FONT>                                    - (Math<a name="line.205"></a>
<FONT color="green">206</FONT>                                                    .floor(7.0 * (year + Math.floor((month + 9.0) / 12.0)) / 4.0))<a
        name="line.206"></a>
<FONT color="green">207</FONT>                                    + Math.floor((275.0 * month) / 9.0) + day<a
        name="line.207"></a>
<FONT color="green">208</FONT>                                    + ((hour + ((minute + (second / 60.0)) / 60.0)) / 24.0)<a
        name="line.208"></a>
<FONT color="green">209</FONT>                                    + 1721013.5 - ((0.5 * extra) / Math.abs(extra)) + 0.5;<a
        name="line.209"></a>
<FONT color="green">210</FONT>                    return JD;<a name="line.210"></a>
<FONT color="green">211</FONT>            }<a name="line.211"></a>
<FONT color="green">212</FONT>    <a name="line.212"></a>
<FONT color="green">213</FONT>            /**<a name="line.213"></a>
<FONT color="green">214</FONT>             * Convert Julian Day to centuries since J2000.0<a name="line.214"></a>
<FONT color="green">215</FONT>             *<a name="line.215"></a>
<FONT color="green">216</FONT>             * @param julian<a name="line.216"></a>
<FONT color="green">217</FONT>             *            The Julian Day to convert<a name="line.217"></a>
<FONT color="green">218</FONT>             * @return the value corresponding to the Julian Day<a name="line.218"></a>
<FONT color="green">219</FONT>             */<a name="line.219"></a>
<FONT color="green">220</FONT>            private static double julianDayToJulianCenturies(double julian) {<a
        name="line.220"></a>
<FONT color="green">221</FONT>                    return (julian - 2451545) / 36525;<a name="line.221"></a>
<FONT color="green">222</FONT>            }<a name="line.222"></a>
<FONT color="green">223</FONT>    <a name="line.223"></a>
<FONT color="green">224</FONT>            /**<a name="line.224"></a>
<FONT color="green">225</FONT>             * Convert centuries since J2000.0 to Julian Day<a name="line.225"></a>
<FONT color="green">226</FONT>             *<a name="line.226"></a>
<FONT color="green">227</FONT>             * @param t<a name="line.227"></a>
<FONT color="green">228</FONT>             *            Number of Julian centuries since J2000.0<a name="line.228"></a>
<FONT color="green">229</FONT>             * @return The Julian Day corresponding to the value of t<a
        name="line.229"></a>
<FONT color="green">230</FONT>             */<a name="line.230"></a>
<FONT color="green">231</FONT>            private static double julianCenturiesToJulianDay(double t) {<a
        name="line.231"></a>
<FONT color="green">232</FONT>                    return (t * 36525) + 2451545;<a name="line.232"></a>
<FONT color="green">233</FONT>            }<a name="line.233"></a>
<FONT color="green">234</FONT>    <a name="line.234"></a>
<FONT color="green">235</FONT>            /**<a name="line.235"></a>
<FONT color="green">236</FONT>             * Calculate the difference between true solar time and mean solar time<a
        name="line.236"></a>
<FONT color="green">237</FONT>             *<a name="line.237"></a>
<FONT color="green">238</FONT>             * @param t<a name="line.238"></a>
<FONT color="green">239</FONT>             *            Number of Julian centuries since J2000.0<a name="line.239"></a>
<FONT color="green">240</FONT>             * @return<a name="line.240"></a>
<FONT color="green">241</FONT>             */<a name="line.241"></a>
<FONT color="green">242</FONT>            private static double equationOfTime(double t) {<a name="line.242"></a>
<FONT color="green">243</FONT>                    double epsilon = obliquityCorrection(t);<a name="line.243"></a>
<FONT color="green">244</FONT>                    double l0 = geomMeanLongSun(t);<a name="line.244"></a>
<FONT color="green">245</FONT>                    double e = eccentricityOfEarthsOrbit(t);<a name="line.245"></a>
<FONT color="green">246</FONT>                    double m = geometricMeanAnomalyOfSun(t);<a name="line.246"></a>
<FONT color="green">247</FONT>                    double y = Math.pow((Math.tan(Math.toRadians(epsilon) / 2)), 2);<a
        name="line.247"></a>
<FONT color="green">248</FONT>    <a name="line.248"></a>
<FONT color="green">249</FONT>                    double eTime = y * Math.sin(2 * Math.toRadians(l0)) - 2 * e<a
        name="line.249"></a>
<FONT color="green">250</FONT>                                    * Math.sin(Math.toRadians(m)) + 4 * e * y<a
        name="line.250"></a>
<FONT color="green">251</FONT>                                    * Math.sin(Math.toRadians(m))<a name="line.251"></a>
<FONT color="green">252</FONT>                                    * Math.cos(2 * Math.toRadians(l0)) - 0.5 * y * y<a
        name="line.252"></a>
<FONT color="green">253</FONT>                                    * Math.sin(4 * Math.toRadians(l0)) - 1.25 * e * e<a
        name="line.253"></a>
<FONT color="green">254</FONT>                                    * Math.sin(2 * Math.toRadians(m));<a
        name="line.254"></a>
<FONT color="green">255</FONT>                    return Math.toDegrees(eTime) * 4;<a name="line.255"></a>
<FONT color="green">256</FONT>            }<a name="line.256"></a>
<FONT color="green">257</FONT>    <a name="line.257"></a>
<FONT color="green">258</FONT>            /**<a name="line.258"></a>
<FONT color="green">259</FONT>             * Calculate the declination of the sun<a name="line.259"></a>
<FONT color="green">260</FONT>             *<a name="line.260"></a>
<FONT color="green">261</FONT>             * @param t<a name="line.261"></a>
<FONT color="green">262</FONT>             *            Number of Julian centuries since J2000.0<a name="line.262"></a>
<FONT color="green">263</FONT>             * @return The Sun's declination in degrees<a name="line.263"></a>
<FONT color="green">264</FONT>             */<a name="line.264"></a>
<FONT color="green">265</FONT>            private static double sunDeclination(double t) {<a name="line.265"></a>
<FONT color="green">266</FONT>                    double e = obliquityCorrection(t);<a name="line.266"></a>
<FONT color="green">267</FONT>                    double lambda = sunsApparentLongitude(t);<a name="line.267"></a>
<FONT color="green">268</FONT>    <a name="line.268"></a>
<FONT color="green">269</FONT>                    double sint = Math.sin(Math.toRadians(e))<a name="line.269"></a>
<FONT color="green">270</FONT>                                    * Math.sin(Math.toRadians(lambda));<a
        name="line.270"></a>
<FONT color="green">271</FONT>                    return Math.toDegrees(Math.asin(sint));<a name="line.271"></a>
<FONT color="green">272</FONT>            }<a name="line.272"></a>
<FONT color="green">273</FONT>    <a name="line.273"></a>
<FONT color="green">274</FONT>            /**<a name="line.274"></a>
<FONT color="green">275</FONT>             * calculate the hour angle of the sun for a morning phenomenon for the<a
        name="line.275"></a>
<FONT color="green">276</FONT>             * given latitude<a name="line.276"></a>
<FONT color="green">277</FONT>             *<a name="line.277"></a>
<FONT color="green">278</FONT>             * @param lat<a name="line.278"></a>
<FONT color="green">279</FONT>             *            Latitude of the observer in degrees<a name="line.279"></a>
<FONT color="green">280</FONT>             * @param solarDec<a name="line.280"></a>
<FONT color="green">281</FONT>             *            declination of the sun in degrees<a name="line.281"></a>
<FONT color="green">282</FONT>             * @param zenithDistance<a name="line.282"></a>
<FONT color="green">283</FONT>             *            zenith distance of the sun in degrees<a name="line.283"></a>
<FONT color="green">284</FONT>             * @return hour angle of sunrise in radians<a name="line.284"></a>
<FONT color="green">285</FONT>             */<a name="line.285"></a>
<FONT color="green">286</FONT>            private static double hourAngleMorning(double lat, double solarDec,<a
        name="line.286"></a>
<FONT color="green">287</FONT>                            double zenithDistance) {<a name="line.287"></a>
<FONT color="green">288</FONT>                    return (Math.acos(Math.cos(Math.toRadians(zenithDistance))<a
        name="line.288"></a>
<FONT color="green">289</FONT>                                    / (Math.cos(Math.toRadians(lat)) * Math.cos(Math<a
        name="line.289"></a>
<FONT color="green">290</FONT>                                                    .toRadians(solarDec))) - Math.tan(Math.toRadians(lat))<a
        name="line.290"></a>
<FONT color="green">291</FONT>                                    * Math.tan(Math.toRadians(solarDec))));<a
        name="line.291"></a>
<FONT color="green">292</FONT>            }<a name="line.292"></a>
<FONT color="green">293</FONT>    <a name="line.293"></a>
<FONT color="green">294</FONT>            /**<a name="line.294"></a>
<FONT color="green">295</FONT>             * Calculate the hour angle of the sun for an evening phenomenon for the<a
        name="line.295"></a>
<FONT color="green">296</FONT>             * given latitude<a name="line.296"></a>
<FONT color="green">297</FONT>             *<a name="line.297"></a>
<FONT color="green">298</FONT>             * @param lat<a name="line.298"></a>
<FONT color="green">299</FONT>             *            Latitude of the observer in degrees<a name="line.299"></a>
<FONT color="green">300</FONT>             * @param solarDec<a name="line.300"></a>
<FONT color="green">301</FONT>             *            declination of the Sun in degrees<a name="line.301"></a>
<FONT color="green">302</FONT>             * @param zenithDistance<a name="line.302"></a>
<FONT color="green">303</FONT>             *            zenith distance of the sun in degrees<a name="line.303"></a>
<FONT color="green">304</FONT>             * @return hour angle of sunset in radians<a name="line.304"></a>
<FONT color="green">305</FONT>             */<a name="line.305"></a>
<FONT color="green">306</FONT>            private static double hourAngleEvening(double lat, double solarDec,<a
        name="line.306"></a>
<FONT color="green">307</FONT>                            double zenithDistance) {<a name="line.307"></a>
<FONT color="green">308</FONT>                    return -hourAngleMorning(lat, solarDec, zenithDistance);<a
        name="line.308"></a>
<FONT color="green">309</FONT>            }<a name="line.309"></a>
<FONT color="green">310</FONT>    <a name="line.310"></a>
<FONT color="green">311</FONT>            /**<a name="line.311"></a>
<FONT color="green">312</FONT>             * Calculate the corrected obliquity of the ecliptic<a name="line.312"></a>
<FONT color="green">313</FONT>             *<a name="line.313"></a>
<FONT color="green">314</FONT>             * @param t<a name="line.314"></a>
<FONT color="green">315</FONT>             *            Number of Julian centuries since J2000.0<a name="line.315"></a>
<FONT color="green">316</FONT>             * @return Corrected obliquity in degrees<a name="line.316"></a>
<FONT color="green">317</FONT>             */<a name="line.317"></a>
<FONT color="green">318</FONT>            private static double obliquityCorrection(double t) {<a name="line.318"></a>
<FONT color="green">319</FONT>                    return meanObliquityOfEcliptic(t) + 0.00256<a name="line.319"></a>
<FONT color="green">320</FONT>                                    * Math.cos(Math.toRadians(125.04 - 1934.136 * t));<a
        name="line.320"></a>
<FONT color="green">321</FONT>            }<a name="line.321"></a>
<FONT color="green">322</FONT>    <a name="line.322"></a>
<FONT color="green">323</FONT>            /**<a name="line.323"></a>
<FONT color="green">324</FONT>             * Calculate the mean obliquity of the ecliptic<a name="line.324"></a>
<FONT color="green">325</FONT>             *<a name="line.325"></a>
<FONT color="green">326</FONT>             * @param t<a name="line.326"></a>
<FONT color="green">327</FONT>             *            Number of Julian centuries since J2000.0<a name="line.327"></a>
<FONT color="green">328</FONT>             * @return Mean obliquity in degrees<a name="line.328"></a>
<FONT color="green">329</FONT>             */<a name="line.329"></a>
<FONT color="green">330</FONT>            private static double meanObliquityOfEcliptic(double t) {<a
        name="line.330"></a>
<FONT color="green">331</FONT>                    return 23 + (26 + (21.448 - t<a name="line.331"></a>
<FONT color="green">332</FONT>                                    * (46.815 + t * (0.00059 - t * (0.001813))) / 60)) / 60;<a
        name="line.332"></a>
<FONT color="green">333</FONT>            }<a name="line.333"></a>
<FONT color="green">334</FONT>    <a name="line.334"></a>
<FONT color="green">335</FONT>            /**<a name="line.335"></a>
<FONT color="green">336</FONT>             * Calculate the geometric mean longitude of the sun<a name="line.336"></a>
<FONT color="green">337</FONT>             *<a name="line.337"></a>
<FONT color="green">338</FONT>             * @param t<a name="line.338"></a>
<FONT color="green">339</FONT>             *            number of Julian centuries since J2000.0<a name="line.339"></a>
<FONT color="green">340</FONT>             * @return the geometric mean longitude of the sun in degrees<a
        name="line.340"></a>
<FONT color="green">341</FONT>             */<a name="line.341"></a>
<FONT color="green">342</FONT>            private static double geomMeanLongSun(double t) {<a name="line.342"></a>
<FONT color="green">343</FONT>                    double l0 = 280.46646 + t * (36000.76983 + 0.0003032 * t);<a
        name="line.343"></a>
<FONT color="green">344</FONT>    <a name="line.344"></a>
<FONT color="green">345</FONT>                    while ((l0 &gt;= 0) &amp;&amp; (l0 &lt;= 360)) {<a
        name="line.345"></a>
<FONT color="green">346</FONT>                            if (l0 &gt; 360) {<a name="line.346"></a>
<FONT color="green">347</FONT>                                    l0 = l0 - 360;<a name="line.347"></a>
<FONT color="green">348</FONT>                            }<a name="line.348"></a>
<FONT color="green">349</FONT>    <a name="line.349"></a>
<FONT color="green">350</FONT>                            if (l0 &lt; 0) {<a name="line.350"></a>
<FONT color="green">351</FONT>                                    l0 = l0 + 360;<a name="line.351"></a>
<FONT color="green">352</FONT>                            }<a name="line.352"></a>
<FONT color="green">353</FONT>                    }<a name="line.353"></a>
<FONT color="green">354</FONT>                    return l0;<a name="line.354"></a>
<FONT color="green">355</FONT>            }<a name="line.355"></a>
<FONT color="green">356</FONT>    <a name="line.356"></a>
<FONT color="green">357</FONT>            /**<a name="line.357"></a>
<FONT color="green">358</FONT>             * Calculate the eccentricity of Earth's orbit<a name="line.358"></a>
<FONT color="green">359</FONT>             *<a name="line.359"></a>
<FONT color="green">360</FONT>             * @param t<a name="line.360"></a>
<FONT color="green">361</FONT>             *            Number of Julian centuries since J2000.0<a name="line.361"></a>
<FONT color="green">362</FONT>             * @return the eccentricity<a name="line.362"></a>
<FONT color="green">363</FONT>             */<a name="line.363"></a>
<FONT color="green">364</FONT>            private static double eccentricityOfEarthsOrbit(double t) {<a
        name="line.364"></a>
<FONT color="green">365</FONT>                    return 0.016708634 - t * (0.000042037 + 0.0000001267 * t);<a
        name="line.365"></a>
<FONT color="green">366</FONT>            }<a name="line.366"></a>
<FONT color="green">367</FONT>    <a name="line.367"></a>
<FONT color="green">368</FONT>            /**<a name="line.368"></a>
<FONT color="green">369</FONT>             * Calculate the geometric mean anomaly of the Sun<a name="line.369"></a>
<FONT color="green">370</FONT>             *<a name="line.370"></a>
<FONT color="green">371</FONT>             * @param t<a name="line.371"></a>
<FONT color="green">372</FONT>             *            Number of Julian centuries since J2000.0<a name="line.372"></a>
<FONT color="green">373</FONT>             * @return the geometric mean anomaly of the Sun in degrees<a
        name="line.373"></a>
<FONT color="green">374</FONT>             */<a name="line.374"></a>
<FONT color="green">375</FONT>            private static double geometricMeanAnomalyOfSun(double t) {<a
        name="line.375"></a>
<FONT color="green">376</FONT>                    return 357.52911 + t * (35999.05029 - 0.0001537 * t);<a
        name="line.376"></a>
<FONT color="green">377</FONT>            }<a name="line.377"></a>
<FONT color="green">378</FONT>    <a name="line.378"></a>
<FONT color="green">379</FONT>            /**<a name="line.379"></a>
<FONT color="green">380</FONT>             * Calculate the apparent longitude of the sun<a name="line.380"></a>
<FONT color="green">381</FONT>             *<a name="line.381"></a>
<FONT color="green">382</FONT>             * @param t<a name="line.382"></a>
<FONT color="green">383</FONT>             *            Number of Julian centuries since J2000.0<a name="line.383"></a>
<FONT color="green">384</FONT>             * @return The apparent longitude of the Sun in degrees<a name="line.384"></a>
<FONT color="green">385</FONT>             */<a name="line.385"></a>
<FONT color="green">386</FONT>            private static double sunsApparentLongitude(double t) {<a name="line.386"></a>
<FONT color="green">387</FONT>                    return sunsTrueLongitude(t) - 0.00569 - 0.00478<a name="line.387"></a>
<FONT color="green">388</FONT>                                    * Math.sin(Math.toRadians(125.04 - 1934.136 * t));<a
        name="line.388"></a>
<FONT color="green">389</FONT>            }<a name="line.389"></a>
<FONT color="green">390</FONT>    <a name="line.390"></a>
<FONT color="green">391</FONT>            /**<a name="line.391"></a>
<FONT color="green">392</FONT>             * Calculate the true longitude of the sun<a name="line.392"></a>
<FONT color="green">393</FONT>             *<a name="line.393"></a>
<FONT color="green">394</FONT>             * @param t<a name="line.394"></a>
<FONT color="green">395</FONT>             *            Number of Julian centuries since J2000.0<a name="line.395"></a>
<FONT color="green">396</FONT>             * @return The Sun's true longitude in degrees<a name="line.396"></a>
<FONT color="green">397</FONT>             */<a name="line.397"></a>
<FONT color="green">398</FONT>            private static double sunsTrueLongitude(double t) {<a name="line.398"></a>
<FONT color="green">399</FONT>                    return geomMeanLongSun(t) + equationOfCentreForSun(t);<a
        name="line.399"></a>
<FONT color="green">400</FONT>            }<a name="line.400"></a>
<FONT color="green">401</FONT>    <a name="line.401"></a>
<FONT color="green">402</FONT>            /**<a name="line.402"></a>
<FONT color="green">403</FONT>             * Calculate the equation of centre for the Sun<a name="line.403"></a>
<FONT color="green">404</FONT>             *<a name="line.404"></a>
<FONT color="green">405</FONT>             * @param centuries<a name="line.405"></a>
<FONT color="green">406</FONT>             *            Number of Julian centuries since J2000.0<a name="line.406"></a>
<FONT color="green">407</FONT>             * @return The equation of centre for the Sun in degrees<a
        name="line.407"></a>
<FONT color="green">408</FONT>             */<a name="line.408"></a>
<FONT color="green">409</FONT>            private static double equationOfCentreForSun(double t) {<a
        name="line.409"></a>
<FONT color="green">410</FONT>                    double m = geometricMeanAnomalyOfSun(t);<a name="line.410"></a>
<FONT color="green">411</FONT>    <a name="line.411"></a>
<FONT color="green">412</FONT>                    return Math.sin(Math.toRadians(m))<a name="line.412"></a>
<FONT color="green">413</FONT>                                    * (1.914602 - t * (0.004817 + 0.000014 * t))<a
        name="line.413"></a>
<FONT color="green">414</FONT>                                    + Math.sin(2 * Math.toRadians(m)) * (0.019993 - 0.000101 * t)<a
        name="line.414"></a>
<FONT color="green">415</FONT>                                    + Math.sin(3 * Math.toRadians(m)) * 0.000289;<a
        name="line.415"></a>
<FONT color="green">416</FONT>            }<a name="line.416"></a>
<FONT color="green">417</FONT>    }<a name="line.417"></a>




























































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